Mr Blair has said his policy has not changed since the energy White Paper two years ago, which left nuclear power on the back burner.

On Wednesday he told BBC Radio 4's Today programme he could not rule out a new generation of civil nuclear power stations.

But he said: "Personally, I find it hard to see how you are going to get consent for that unless you deal with the issue of the public concern over waste and you deal with the issue of cost."

Carbon neutral

There have been reports that if re-elected, Mr Blair would raise the issue when the government responds to its climate change policy review in the summer.

The government says the UK will meet the Kyoto targets on climate change but says it has slipped behind its own tougher targets.

Nuclear power is almost "carbon neutral" - government figures suggest nuclear generation reduces national carbon emissions by between seven and 14%.

But campaigners say the risk of accidents, and the toxic waste it creates, mean it is not acceptable as an alternative to oil and coal.

The Lib Dems' environment spokesman Norman Baker has said relying on nuclear power to tackle climate change is "like jumping from the frying pan to the fire".

The Conservatives have previously said they are in favour in principle of a new generation of nuclear power stations.

Last week party leader Michael Howard said they did not have the facts and figures on waste disposal and cost to make a decision, but said there may be a strong case for a national review of nuclear stations.